Jaynes

Probability theory was in its infancy in Bayes’s day. Strange as it may seem, before the seventeenth century nobody could calculate even such simple chances as that of a normal coin landing five heads in a row. It wasn’t that the information wouldn’t have been useful. There was plenty of gambling before modernity. But somehow no one could get their head around probabilities. As Ian Hacking put in his groundbreaking The Emergence of Probability (1975), someone in ancient Rome “with only the most modest knowledge of probability mathematics could have won himself the whole of Gaul in a week”.

Julian Jaynes is almost certainly wrong in the details of his “bicameral mind” theorizing, but he’s not wrong in the general idea that the human psyche and cognitive tools (and perhaps consciousness itself) have changed extremely radically from ancient times until now — perhaps several times.

I’m a mathematical moron, and probability makes intuitive sense to me and calculating it is fairly easy. That before 1600 or so no one could really do that is pretty astounding, but also expected in a way. Their minds and their culture just did not work that way, so that sort of probability calculation would have been prima facie senseless to them and to the ancients.